This is an area I hadn't considered. Thank you. Maybe you can explain this passage in Genesis to me, and clear up my confusion.
" And the Lord God said, Behold, the man is become as one of us, to know good and evil: and now, lest he put forth his hand, and take also of the tree of life, and eat, and live for ever": Gen.3:22
Who is US
To clear up your confusion it would be necessary for you to approach the Bible with a belief that it is truth. If you don't believe that, it will never make sense.
1Cor 1:18,
For the preaching of the cross is to them that perish foolishness; but unto us which are saved it is the power of God.
If you are sincerely searching for truth, God will make it know to you via the scriptures. Regardless, I'll tell try to answer your questions the best I can. Google "royal we." Tradition may say trinity, but I addressed tradition vs truth earlier.
and why would God not want his creation to live forever? I'm simply curious.
After their disobedience life took a bad turn for Adam and Eve.
Gen 3:16-19,
16 Unto the woman he said, I will greatly multiply thy sorrow and thy conception; in sorrow thou shalt bring forth children; and thy desire [shall be] to thy husband, and he shall rule over thee.
17 And unto Adam he said, Because thou hast hearkened unto the voice of thy wife, and hast eaten of the tree, of which I commanded thee, saying, Thou shalt not eat of it: cursed [is] the ground for thy sake; in sorrow shalt thou eat [of] it all the days of thy life;
18 Thorns also and thistles shall it bring forth to thee; and thou shalt eat the herb of the field;
19 In the sweat of thy face shalt thou eat bread, till thou return unto the ground; for out of it wast thou taken: for dust thou [art], and unto dust shalt thou return.
Had they eaten of the tree of life they would have gone on for eternity in their fallen state. That's not what God wanted. He made plans to give them a new body in a new heaven and earth which will come to pass in the book of Revelations. To get the new body, the old one had to die, hence the need to prevent them from living forever in their fallen body state. The 15th chapter of 1 Corinthians goes into some detail if you are curious.
So if you believe the Bible is truth, these answers should make sense. If you don't believe it, they may not, but it's the best I can do. Take care...